IGX Thor Developer Kit Mini – No Display Output After Ubuntu Boot (HDMI/DP Blank, DRM/NVIDIA Initialization Issue)

Robotics & Edge Computing IGX Systems IGX Thor Support
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1

Hi NVIDIA Team,

I am Goutham Gandhi, currently working with the IGX Thor Developer Kit Mini.

I downloaded the IGX ISO from IGX SW 2.0 Production Release and followed the official installation guide:
https://docs.nvidia.com/igx/user-guide/2.0/OV/thor/base-os-t5000.html#install-igx-thor-t5000

The installation completed successfully and the system rebooted without any issues. I was able to complete the NVIDIA OOBE setup and create a user account and password via UART.

However, after this step, the display is not working over both HDMI and DisplayPort. I have tested with both LG and Dell monitors and with different cables, observing same issue. During boot, the display briefly shows the Ubuntu boot selection screen. But after selecting Ubuntu, the screen goes blank and goes into sleep mode.

Despite this, I am able to log in and access the system via UART without any problems.
While reviewing the logs, I noticed display-related errors even before the OOBE setup stage. Below are some relevant error messages:

image

It appears there may be an issue with DRM/NVIDIA display initialization. We found similar issue been reported for IGX T7000 - Igx_sw_2.0_ea on IGX Thor T7000 installation - however we couldn’t find any solution for this.

Could you please help identify what might be causing this display issue? I have attached the complete logs for reference.

Best Regards,
Goutham

IGX_flash.log (1.6 MB)

3

Hi goutham.gandhi,

Do you download the IGX OS ISO from IGX Download Center | NVIDIA Developer?

Please share the current dmesg as you can still access the system with serial console.

4

Hi Kevin,

Yes, I downloaded the IGX OS ISO from the NVIDIA Developer Download Center.

image
image800×449 55.2 KB

and followed the official installation guide:

https://docs.nvidia.com/igx/user-guide/2.0/OV/thor/base-os-t5000.html#install-igx-thor-t5000

As suggested, I have captured the current dmesg logs using the serial console (UART). Please find the attached dmesg output for your reference [IGX_dmesg.log] .

Kindly let me know if any additional logs or specific debug information are required.

IGX_dmesg.log (176.4 KB)

5

I cannot reproduce the similar issue on my IGX Thor devkit mini.
Have you tried using flash script(instead of using BaseOS ISO) to setup it?

6

Hi Kevin,

Following your suggestion, I tried flashing the board using the flash script instead of the BaseOS ISO. I also ensured that the Safety MCU was flashed according to the SEP Developer Guide. I am seeing significant differences in how the system initializes between these two methods.

When using the Flash Script setup, the system is fully functional. HDMI output works as expected, and SMCU telemetry is completely operational. Specifically, print_telemetry confirms that the Linux/SPI-Server is responding, and thermal data is being successfully received from the CCPLEX. This validates that the MCU communication and the SPI-based telemetry path are healthy in this configuration.

However, the BaseOS ISO setup remains problematic. After reflashing with the ISO, now the HDMI is working, however - SMCU telemetry fails entirely. Running print telemetry returns a “Data NOT AVAILABLE” status.

I have a few specific questions regarding the expected behavior for the IGX Thor:

Initial Bring-up: For a fresh IGX Thor Developer Kit Mini, is the flash script required for the initial bring-up, or is the BaseOS ISO intended to be a standalone solution?
Service Availability: why print telemetry fails upon using ISO? Should services such as nv-spi-server, nv-ccplex-telemetry, and nv-system-control be enabled by default in the BaseOS ISO? If they are not, could you please help me the configuration step required to enable MCU communication when using the ISO method?

In addition, Upon using IGX OS (ISO) stack and would like clarification on the recommended workflow for integrating custom drivers and Device Tree changes. Specifically, how should we load and manage loadable kernel modules (LKMs), and in cases where a driver requires Device Tree modifications (such as camera integration), how can we provide or update the DTB within the IGX OS environment, given that DTB files and boot configurations (e.g., extlinux) are not exposed in the filesystem?

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Your guidance on the correct workflow for integrating such drivers and Device Tree changes in IGX OS would be very helpful.

Looking forward to your response.

7

Could you clarify your requirements?
Please let us know if you are developing a custom driver for the IGX Thor devkit mini, designing a carrier board for the IGX T5000, or have specific safety requirements.

For an IGX Thor Dev Kit Mini on IGX-SW 2.0, the IGX OS BaseOS ISO is a valid standalone bring-up path. L4T flash scripts are mainly needed for BSP/JetPack or SEP BSP flows, or if you intentionally want a custom QSPI / safety layout.

print_telemetry only works when the SEP userspace stack is present (nv-spi-server, nv-ccplex-telemetry, nv-system-control + /opt/nvidia/ccplex_sf/...).

  • Your flash-script setup = L4T + SEP → those services exist and are enabled → “Data AVAILABLE”.
  • Plain IGX OS ISO does not include SEP, so Linux never answers the SPI telemetry request → “Data NOT AVAILABLE”.
8

Hi Kevin,

Thank you for your comments and clarification.

We are planning to develop a custom carrier board using the IGX Thor T5000 module and intend to integrate cameras and other peripherals into the system.

Before proceeding with the custom carrier board design, we are currently evaluating the IGX Thor Developer Kit Mini that we recently purchased. As part of this evaluation, we have started exploring the available software stack options and are currently working with the IGX OS (.iso) stack.

We already have prior experience working with the JetPack stack on AGX Orin and IGX Thor. However, the IGX OS (.iso) environment is new to us, and we are trying to understand the recommended workflow for integrating our custom driver into this system.

Specifically, we would like to understand:

  • How to load and manage our custom driver (.ko) in IGX OS

  • How Device Tree handling works in this environment, since we could not find DTB files or boot configurations similar to JetPack

Looking for the steps to load our drivers as LKM’s. We would appreciate your guidance and support on this.

Regards,

Goutham

9

Could you share the result of the following command on your board?

$ sudo i2cdump -f -y 1 0x56

For the custom board design on IGX Thor T5000, we would suggest using the BSP package to flash your board as you may need to customize the board config/kernel image/device tree..etc.

You can refer to Customizing the ISO Image — NVIDIA IGX Developer Guide for this use case.

If your board is setup with ISO, there’s no exlinux.conf like you flashing with script.
You need to reflash the QSPI to update the device tree in use.
(i.e. it will use UEFI-DTB by default in thise case)